In digital communications networks, packet processing refers to the wide variety of techniques that are applied to a packet of data or information as it moves through the various network elements of a communications network. There are two broad classes of packet processing techniques that align with the standardized network subdivisions of control plane and data plane. The techniques are applied to either control information contained in a packet which is used to transfer the packet safely and efficiently from origin to destination or the data content (frequently called the payload) of the packet, which is used to provide some content-specific transformation or take a content-driven action. Within any network enabled device (e.g. router, switch, firewall, network element or terminal such as a computer or smartphone) it is the packet processing subsystem that manages the traversal of the multi-layered network or protocol stack from the lower, physical and network layers all the way through to the application layer.
Quality of service (QoS) is the description or measurement of the overall performance of a service, such as a computer network or a cloud computing service, particularly the performance seen by the users of the network. To quantitatively measure quality of service, several related aspects of the network service are often considered, such as packet loss, bit rate, throughput, transmission delay, availability, jitter, etc.
In the field of computer networking and other packet-switched telecommunication networks, quality of service refers to traffic prioritization and resource reservation control mechanisms rather than the achieved service quality. Quality of service is the ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow.
Advances have been made in providing appropriate QoS in networks, but existing approaches are not optimized to meet deadlines originating from service level agreements (SLAs).